Preparation And Performance Of Anderson-type Polyoxometalates Based Composite Photocatalysts

Energy shortage and environmental pollution caused by the massive use of fossil fuels are two important problems,which have been widely concerned by researchers all over the world.Photocatalysis technology is considered to have great potentials in solving energy and environmental problems.The composition of fuel oil contains a large number of sulfur compounds（thiophene and its derivatives）,and the combustion process releases a large number of toxic sulfides（such as sulfur dioxide）,which will cause environmental acidification and ecological damage.China requires the content of S less than 10 ppm.At the same time,with the extensive utilize of petroleum as the raw material of fuel oil production,people also have a great demand for fossil fuels.As a non-renewable resource,there will be a shortage of fossil fuels in the future,which will bring a seriously challenges to the sustainable development of humanbeing.Biomass can be used as one of the potential substitutes for petroleum and realize the replacement of fossil energy with renewable carbon raw materials.Therefore,the desulfurization of fuel oil and the exploitation of biomass resources through photocatalysis technology are of great significance to the sustainable development of mankind.In this work,firstly,Anderson-type Polyoxometalate（POM）was loaded on different carbon-based active supports to study their photocatalytic performance.Carbon materials have a large specific surface area and strong adsorption,which is conducive to the loading of POM and the exposure of active sites after loading.Different carbon-based carriers include carbon prepared from biomass derivatives grapefruit peel and coffee grounds,as well as common carbon-based materials such as carbon nanotubes,graphene and activated carbon.The desulfurization performance of different POM loaded on carbon-based materials was investigated.It was found that the 15%Cu Mo₆/C（activated carbon）could achieve a DBT removal efficiency of 95.3%at 3 h in hydrogen peroxide as an oxidant achieving good photocatalytic desulfurization effect.Due to weak response to visible light of single carbon material,semiconductor composite carbon nitride was further introduced.The POM is loaded on the semiconductor composite to investigate photocatalytic performance by combining semiconductor properties and the advantages of Anderson type polyoxometalate.In this work,Anderson type polyoxometalate（NH₄）₄Cu Mo₆O₂₄ was immobilizated on Ti O₂/g-C₃N₄ nanocomposites was successfully synthesized a novel multiphase heterojunction nano-catalyst（NH₄）₄Cu Mo₆O₂₄/Ti O₂/g-C₃N₄（Cu Mo₆/TCN）.The heterostructure facilitates the effective transfer of electrons and promotes the formation of·OH,and the DBT removal reached 98.3%within 3 h.It’s a photocatalytic desulfurization catalyst with potential application value.The catalyst was applied to photocatalytic oxidative desulfurization and achieved 98.3%DBT desulfurization rate within 3 h,showing high catalytic activity.It is a potential photocatalytic material for removing sulfur-containing sulfur compounds.In the third part,the Anderson type POM is introduced into the system using terpolymer sulfide as carrier,which has a good respose to visible light.An electronic bridge was constructed using the rich structure of POM to accelerate the transfer of electrons.Under the condition of stable conversion rate,the selectivity of DFF is as high as 98%,which almost realizes the goal of complete oxidation of the converted part of HMF to DFF.This provides a possible path to achieve efficient use of biomass.In this work,Anderson type POM is loaded on different types of active carriers,which realize the efficient utilization of solar energy from the perspectives of diesel desulfurization and deep utilization of biomass.It supports sustainable development by addressing environmental pollution and using renewable resources.